Specifications

Device Driver Entry Points
Controller Initialization Routine
Exit
The controller initialization routine returns control to its caller with an RSB
instruction.
Description
Some controllers require initialization when the system’s driver-loading routine
loads the driver and when the system is recovering from a power failure.
Depending on the device, a controller initialization routine performs any and
all of the following actions:
• Determine whether it is being called as a result of a power failure by
examining the power bit (UCB$V_POWER in UCB$L_STS) in the UCB. A
controller initialization routine may want to perform or avoid specific tasks
when servicing a power failure.
• Clear error-status bits in device registers.
• Enable controller interrupts.
• Allocate resources that must be permanently allocated to the controller.
• If the controller is dedicated to a single-unit device, such as a printer, fill in
IDB$L_OWNER and set the online bit (UCB$V_ONLINE in UCB$L_STS).
• For generic VAXBI devices, initialize BIIC and device hardware.
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